Welcome to the forum and congratulations on some very beautiful portraits of your granddaughters. As a photographer who from time to time also uses my SX50 for studio portraiture, I can appreciate your work.

What I like about the SX50 is that when using my full frame Canon dSLR, I can easily transfer the ST-E2 slave between cameras and use the same lighting set-up (2x 580 and 1x 430, with or without softboxes). I find the SX50 to give very pleasing results, both in skin tones and skin texture, at the 14mm to 18mm focal length (85mm to 100mm full frame) for "formal" portraiture.

I'm interested in your set-up. What lights did you use and how did you fire them?